Multiple custom Network Conditioner profiles

Hi there.

I really like the new feature of Network Conditioner in Parallels Desktop 18. However I notice one inconvenience: I can only have one "custom" profile. It would be helpful to have multiple custom profiles that I can switch between.

Also it would be nice to have more features, akin to what `tc qdisc netem` offers, like adding random variation to delay or reordering and duplication of packets.